package glredbook12x;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.nio.*;
import javax.media.opengl.*;
import javax.media.opengl.glu.*;
import com.sun.opengl.util.*;
/**
* Use various 2D convolutions filters to find edges in an image.
*
* @author Kiet Le (Java port)
*/
public class convolution
extends JFrame
implements GLEventListener//
, KeyListener //
// , MouseListener //
// , MouseMotionListener //
// , MouseWheelListener //
{
private GLCapabilities caps;
private GLCanvas canvas;
private KeyEvent key;
//
private ByteBuffer pixels;
// private int width; not reference as params...
// private int height;...as are all Java primitives
private Dimension dim = new Dimension(0, 0);
private float horizontal[][] =
{
{ 0, -1, 0 },
{ 0, 1, 0 },
{ 0, 0, 0 } };
private float vertical[][] =
{
{ 0, 0, 0 },
{ -1, 1, 0 },
{ 0, 0, 0 } };
private float laplacian[][] =
{
{ -0.125f, -0.125f, -0.125f },
{ -0.125f, 1.0f, -0.125f },
{ -0.125f, -0.125f, -0.125f } };
private FloatBuffer horizontalBuf = BufferUtil
.newFloatBuffer(horizontal.length * horizontal[0].length);
private FloatBuffer verticalBuf = BufferUtil
.newFloatBuffer(vertical.length * vertical[0].length);
private FloatBuffer laplacianBuf = BufferUtil
.newFloatBuffer(laplacian.length * laplacian[0].length);
{
for (int i = 0; i < 3; i++)
{
horizontalBuf.put(horizontal[i]);
verticalBuf.put(vertical[i]);
laplacianBuf.put(laplacian[i]);
}
horizontalBuf.rewind();
verticalBuf.rewind();
laplacianBuf.rewind();
}
public convolution()
{
super("convolution");
caps = new GLCapabilities();
canvas = new GLCanvas(caps);
canvas.addGLEventListener(this);
canvas.addKeyListener(this);
add(canvas);
}
public void run()
{
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(640, 480);
setLocationRelativeTo(null);
setVisible(true);
canvas.requestFocusInWindow();
}
public static void main(String[] args)
{
new convolution().run();
}
public void init(GLAutoDrawable drawable)
{
GL gl = drawable.getGL();
gl.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, 1);
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
if (gl.isExtensionAvailable("GL_ARB_imaging"))
{
if (gl.isFunctionAvailable("glConvolutionFilter2D"))
{
System.out.println("Using the horizontal filter");
gl.glConvolutionFilter2D(GL.GL_CONVOLUTION_2D, GL.GL_LUMINANCE, //
3, 3, GL.GL_LUMINANCE, GL.GL_FLOAT, horizontalBuf);
gl.glEnable(GL.GL_CONVOLUTION_2D);
}
}
else
{
String msg = "GL_ARB_imaging (optional) subset is is not available.";
setTitle(getTitle() + " GL_ARB_imaging not available :(");
System.err.println(msg);
add(new JLabel(msg), BorderLayout.NORTH);
SwingUtilities.updateComponentTreeUI(this); }
pixels = readImage("Data/leeds.bin", dim);
System.out.println(pixels.toString());
}
public void display(GLAutoDrawable drawable)
{
GL gl = drawable.getGL();
gl.glClear(GL.GL_COLOR_BUFFER_BIT);
if (key != null) switch (key.getKeyChar()) {
case 'h':
System.out.println("Using a horizontal filter");
gl.glConvolutionFilter2D(GL.GL_CONVOLUTION_2D, GL.GL_LUMINANCE, //
3, 3, GL.GL_LUMINANCE, GL.GL_FLOAT, horizontalBuf);
break;
case 'v':
System.out.println("Using the vertical filter\n");
gl.glConvolutionFilter2D(GL.GL_CONVOLUTION_2D, GL.GL_LUMINANCE, //
3, 3, GL.GL_LUMINANCE, GL.GL_FLOAT, verticalBuf);
break;
case 'l':
System.out.println("Using the laplacian filter\n");
gl.glConvolutionFilter2D(GL.GL_CONVOLUTION_2D, GL.GL_LUMINANCE, //
3, 3, GL.GL_LUMINANCE, GL.GL_FLOAT, laplacianBuf);
break;
}// key sw
gl.glRasterPos2i(1, 1);
gl.glDrawPixels(dim.width, dim.height, //
GL.GL_RGB, GL.GL_UNSIGNED_BYTE, pixels);
gl.glFlush();
}
public void reshape(GLAutoDrawable drawable, int x, int y, int w, int h)
{
GL gl = drawable.getGL();
gl.glViewport(0, 0, w, h);
gl.glMatrixMode(GL.GL_PROJECTION);
gl.glLoadIdentity();
gl.glOrtho(0, w, 0, h, -1.0, 1.0);
gl.glMatrixMode(GL.GL_MODELVIEW);
}
public void displayChanged(GLAutoDrawable drawable, boolean modeChanged,
boolean deviceChanged)
{
}
/**
* Reads an image from an archived file and return it as ByteBuffer object.
*
* @author Mike Butler, Kiet Le
*/
private ByteBuffer readImage(String filename, Dimension dim)
{
if (dim == null) dim = new Dimension(0, 0);
ByteBuffer bytes = null;
try
{
DataInputStream dis = new DataInputStream(getClass().getClassLoader()
.getResourceAsStream(filename));
dim.width = dis.readInt();
dim.height = dis.readInt();
System.out.println("Creating buffer, width: " + dim.width + " height: "
+ dim.height);
// byte[] buf = new byte[3 * dim.height * dim.width];
bytes = BufferUtil.newByteBuffer(3 * dim.width * dim.height);
for (int i = 0; i < bytes.capacity(); i++)
{
bytes.put(dis.readByte());
}
dis.close();
}
catch (Exception e)
{
e.printStackTrace();
}
bytes.rewind();
return bytes;
}
public void keyTyped(KeyEvent key)
{
}
public void keyPressed(KeyEvent key)
{
this.key = key;
switch (key.getKeyChar()) {
case KeyEvent.VK_ESCAPE:
System.exit(0);
break;
}
canvas.display();
}
public void keyReleased(KeyEvent key)
{
}
}
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